The Contagion Spreading—Riotous Demonstrations in Westchester County, Brooklyn, Jersey City, Staten Island and Jamaica. Increased Preparations by the Authorities.

INCIDENTS, CASUALTIES, &o., &o.

The ravages of the mob which commenced its diabolical career on Monday are not yet ended, and it is impossible to say at the hour of going to press this morning whether the worst has yet been seen. All through Tuesday night marauding bands of plunderers in greater or less numbers, continued to commit their depredation in various parts of the City, but at daylight yesterday morning they had generally dispersed, and there was a fair prospect of a speedy restoration of quiet and order. The authorities, both State and military, appeared to concede the riot as substantially subdued, and after a consultation early in the forenoon, between the MAYOR OPKYKE, GOV. SEYMOUR AND GEN. WOOL, at the St. Nicholas Hotel, the following proclamation was issued from the Mayor’s office:

DOINGS OF GOV. SEYMOUR

GOV. SEYMOUR has established his Headquarters at the St. Nicholas Hotel, where Gen. WOOL resides, and he spent most of the day yesterday in consultation with the General and with the City authorities as to the speediest mode of restoring the public peace. He feels confident that the mob has no organization, and regards them as roving ladds of lawless desperadoes pent on plunder. He is anxious that the people should follow the instructions set forth in his proclamation of Tuesday, and organize themselves into armed squads in their respective neighborhoods to protect their property and the peace of the City. The following letter, written by the governor on Monday, may be of interest:

New York, 13th July, 1863.

My Dear sir: I have received your note about the draft. On Saturday last I sent my Adjunct General to Washington for the purpose of urging a suspension of the draft, for I know that the City of New York can furnish its full quota by volunteering. I have received a dispatch from Gen. S_____ that the Draft is suspended. There is no doubt that the conscription is postponed. I learn this from a number of sources. If I get any information or a change of policy at Washington, I will let you know. Truly yours,

HORATIO SEYMOUR

Hon. Samuel Sloan, President of the Hudson River Railroad Company, New York.

The conjectures of the Governor contained in the above as to the postponement of the drat, were confirmed yesterday by the following note received from Assistant Provost Marshal Nugent:

THE DRAFT

New York, July 15, 1863

The draft has been suspended in New York City and Brooklyn.

ROBERT NUGENT, Colonel and Assistant Provost Marshall General.

THE MURDER OF COLORED PEOPLE IN THOMPSON AND SULLIVAN STREETS

At a late hour on Tuesday night the mob made an attack upon the tenement houses, occupied by colore people, in Sullivan and Thompson-streets. For three hours, and up to two o’clock yesterday morning there was what may be truly said to be a “reign of terror” throughout all that portion of the City. Several buildings were fired, and a large number of colored persons were beaten so badly that they lay insensible in the street for hours after. Two colored children at No. 59 Thompson-street were shot and instantly killed. Men, women and children, in large numbers flocked to the Eighth Precinct Station-house for protection. Over one hundred of them were there accomodated with temporary shelter.

THE SACKING OF BUILDINGS IN AVENUES B AND A.

Late in the afternoon of Tuesday the hardware store of AARON HARPER, situated at No. 78 Avenue B, was attacked by the rioters. The front doors were burst open, the windows of the building were all smashed with stones and brickbats, and all the goods and valuables were taken away. The store was completely stripped, nothing of valued being left.

From this place the mob repaired to the lock and gunsmith store of JOHN WAGNER, No. 66 Avenue A. This was also broken open, sacked and robbed of the contents, and afterward the property was distributed among the rioters.

Late on Tuesday night the tailoring establishment of THOMAS EGAN, of Avenue A, was forced open by the mob. The doors and windows were all destroyed, and the place completely stripped of its contents.

In the present disturbed condition of the City, I will appeal not only to them, but t all persons who love God and revere the holy Catholic religion which they profess, to respect also the laws of man and the peace of society, to retire to their homes with as little delay as possible, and disconnect themselves from the seemingly deliberate intention to disturb the peace and social rights of the citizens of New York. If they are Catholics, or of such of them as are Catholics, I ask, for God’s sake—for the sake of their holy religion—for my sake, if they have any respect for the Episcopal authority—to dissolve their associations with reckless men, who have little regard either of Divine or human laws.